Stepwise phosphorylation and SUMOylation of PIDD1 drive PIDDosome assembly in response to DNA repair failure.

SUMOylation regulates numerous cellular stress responses, yet targets in the apoptotic machinery remain elusive. We show that a single, DNA damage-induced monoSUMOylation event controls PIDDosome (PIDD1/RAIDD/caspase-2) formation and apoptotic death in response to unresolved DNA interstrand crosslinks (ICLs). SUMO-1 conjugation occurs on conserved K879 in the PIDD1 death domain (DD); is catalyzed by PIAS1 and countered by SENP3; and is triggered by ATR phosphorylation of neighboring T788 in the PIDD1 DD, which enables PIAS1 docking.

National burden of rheumatoid arthritis in Canada, 1990-2019: findings from the Global Burden of Disease Study 2019 - a GBD collaborator-led study.

Objective: The objectives of this study were: (1) to describe burden of rheumatoid arthritis (RA) and trends from 1990 to 2019 using the Global Burden of Diseases, Injuries and Risk Factors Study (GBD) data, (2) to describe age and sex differences in RA and (3) to compare Canada's RA burden to that of other countries.

Methods: Disease burden indicators included prevalence, mortality, years of life lost (YLLs), years lived with disability (YLDs) and disability-adjusted life-years (DALYs). GBD estimated fatal and non-fatal outcomes using published literature, survey data and health insurance claims.

A noncanonical IRAK4-IRAK1 pathway counters DNA damage-induced apoptosis independently of TLR/IL-1R signaling.

Interleukin-1 receptor (IL-1R)-associated kinases (IRAKs) are core effectors of Toll-like receptors (TLRs) and IL-1R in innate immunity. Here, we found that IRAK4 and IRAK1 together inhibited DNA damage-induced cell death independently of TLR or IL-1R signaling. In human cancer cells, IRAK4 was activated downstream of ATR kinase in response to double-strand breaks (DSBs) induced by ionizing radiation (IR).

Lycopene Supplementation to Serum-Free Maturation Medium Improves In Vitro Bovine Embryo Development and Quality and Modulates Embryonic Transcriptomic Profile.

Bovine embryos are typically cultured at reduced oxygen tension to lower the impact of oxidative stress on embryo development. However, oocyte in vitro maturation (IVM) is performed at atmospheric oxygen tension since low oxygen during maturation has a negative impact on oocyte developmental competence. Lycopene, a carotenoid, acts as a powerful antioxidant and may protect the oocyte against oxidative stress during maturation at atmospheric oxygen conditions.

Effect of lycopene supplementation to bovine oocytes exposed to heat shock during in vitro maturation.

We investigated the effect of the antioxidant lycopene supplemented into the in vitro maturation medium (TCM-199 with 20 ng/mL epidermal growth factor and 50 mg/mL gentamycin) in a heat shock (HS) model to mimic in vivo heat stress conditions. Bovine cumulus-oocyte complexes were supplemented with 0.2 μM lycopene (or not supplemented; control) under HS (40.

Sulfopin is a covalent inhibitor of Pin1 that blocks Myc-driven tumors in vivo.

The peptidyl-prolyl isomerase, Pin1, is exploited in cancer to activate oncogenes and inactivate tumor suppressors. However, despite considerable efforts, Pin1 has remained an elusive drug target. Here, we screened an electrophilic fragment library to identify covalent inhibitors targeting Pin1's active site Cys113, leading to the development of Sulfopin, a nanomolar Pin1 inhibitor.

Crossbreeding effect of double-muscled cattle on in vitro embryo development and quality.

Nowadays, several developing countries have started to breed double-muscled cattle to their autochthonous cattle to improve meat production. However, the developmental competence of the resultant crossbreeding embryos is unknown. The objective of this study was to evaluate the effect of crossbreeding double-muscled (Belgian Blue; BB) semen with beef (Limousin; LIM) and dairy (Holstein-Friesian; HF) derived oocytes on embryo development and quality, using purebred BB as a control (BB oocytes fertilized by BB sperm).

Targeting the Innate Immune Kinase IRAK1 in Radioresistant Cancer: Double-Edged Sword or One-Two Punch?

Antitumor immunity has emerged as a favorable byproduct of radiation therapy (RT), whereby tumor-associated antigens released from irradiated cells unleash innate and adaptive attacks on tumors located both within and outside the radiation field. RT-induced immune responses further provide actionable targets for overcoming tumor resistance to RT (R-RT); immunotherapy (IT) with checkpoint inhibitors or Toll-like receptor (TLR) agonists can markedly improve, if not synergize with, RT in preclinical models, and several of these drugs are currently investigated as radiosensitizers in patients. In an unbiased chemical-genetic screen in a zebrafish model of tumor R-RT, we unexpectedly found that Interleukin 1 Receptor-Associated Kinase 1 (IRAK1), a core effector of TLR-mediated innate immunity, also functions in live fish and human cancer models to counter RT-induced cell death mediated by the PIDDosome complex (PIDD-RAIDD-caspase-2).

How Cells Handle DNA Breaks during Mitosis: Detection, Signaling, Repair, and Fate Choice.

Mitosis is controlled by a complex series of signaling pathways but mitotic control following DNA damage remains poorly understood. Effective DNA damage sensing and repair is integral to survival but is largely thought to occur primarily in interphase and be repressed during mitosis due to the risk of telomere fusion. There is, however, increasing evidence to suggest tight control of mitotic progression in the incidence of DNA damage, whether induced in mitotic cells or having progressed from failed interphase checkpoints.

An IRAK1-PIN1 signalling axis drives intrinsic tumour resistance to radiation therapy.

Drug-based strategies to overcome tumour resistance to radiotherapy (R-RT) remain limited by the single-agent toxicity of traditional radiosensitizers (for example, platinums) and a lack of targeted alternatives. In a screen for compounds that restore radiosensitivity in p53 mutant zebrafish while tolerated in non-irradiated wild-type animals, we identified the benzimidazole anthelmintic oxfendazole. Surprisingly, oxfendazole acts via the inhibition of IRAK1, a kinase thus far implicated in interleukin-1 receptor (IL-1R) and Toll-like receptor (TLR) immune responses.

Direct pro-apoptotic role for NPM1 as a regulator of PIDDosome formation.

Despite being frequently mutated or deregulated in acute myeloid leukemia (AML) and many other cancers, the mechanisms by which nucleophosmin (NPM1) regulates oncogenesis remain elusive. We found that NPM1 plays a direct and conserved role in DNA damage-induced assembly of the PIDDosome complex, the activating platform for caspase-2. This function is carried in the nucleolus and is essential for caspase-2-mediated apoptosis in response to a variety of DNA injuries.

NPM1 directs PIDDosome-dependent caspase-2 activation in the nucleolus.

The PIDDosome (PIDD-RAIDD-caspase-2 complex) is considered to be the primary signaling platform for caspase-2 activation in response to genotoxic stress. Yet studies of PIDD-deficient mice show that caspase-2 activation can proceed in the absence of PIDD. Here we show that DNA damage induces the assembly of at least two distinct activation platforms for caspase-2: a cytoplasmic platform that is RAIDD dependent but PIDD independent, and a nucleolar platform that requires both PIDD and RAIDD.

A mitosis-sensing caspase activation platform? New insights into the PIDDosome.

In contrast to the apoptosome and death-inducing signaling complex, the PIDDosome remains an orphan caspase activation platform unassigned to a specific apoptotic pathway. We found that DNA damage-induced PIDDosome formation is blocked by the mitotic checkpoint factor BUBR1 (budding uninhibited by benzimidazole-related 1), via a direct interaction that disrupts the PIDDosome core scaffold. This inhibition occurs at the kinetochore, thus physically connecting the mitotic and apoptotic machineries.

An Inhibitor of PIDDosome Formation.

The PIDDosome-PIDD-RAIDD-caspase-2 complex-is a proapoptotic caspase-activation platform of elusive significance. DNA damage can initiate complex assembly via ATM phosphorylation of the PIDD death domain (DD), which enables RAIDD recruitment to PIDD. In contrast, the mechanisms limiting PIDDosome formation have remained unclear.

PIDD death-domain phosphorylation by ATM controls prodeath versus prosurvival PIDDosome signaling.

Biochemical evidence implicates the death-domain (DD) protein PIDD as a molecular switch capable of signaling cell survival or death in response to genotoxic stress. PIDD activity is determined by binding-partner selection at its DD: whereas recruitment of RIP1 triggers prosurvival NF-κB signaling, recruitment of RAIDD activates proapoptotic caspase-2 via PIDDosome formation. However, it remains unclear how interactor selection, and thus fate decision, is regulated at the PIDD platform.

Air quality impact assessment of at-berth ship emissions: Case-study for the project of a new freight port.

This work is intended to assess the impact on local air quality due to atmospheric emissions from port area activities for a new port in project in the Mediterranean Sea. The sources of air pollutants in the harbour area are auxiliary engines used by ships at berth during loading/offloading operations. A fleet activity-based methodology is first applied to evaluate annual pollutant emissions (NO(X), SO(X), PM, CO and VOC) based on vessel traffic data, ships tonnage and in-port hotelling time for loading/offloading operations.

CHK1 inhibition as a strategy for targeting Fanconi Anemia (FA) DNA repair pathway deficient tumors.

Background: DNA repair deficient tumor cells have been shown to accumulate high levels of DNA damage. Consequently, these cells become hyper-dependent on DNA damage response pathways, including the CHK1-kinase-mediated response. These observations suggest that DNA repair deficient tumors should exhibit increased sensitivity to CHK1 inhibition.

Chk1 suppresses a caspase-2 apoptotic response to DNA damage that bypasses p53, Bcl-2, and caspase-3.

Evasion of DNA damage-induced cell death, via mutation of the p53 tumor suppressor or overexpression of prosurvival Bcl-2 family proteins, is a key step toward malignant transformation and therapeutic resistance. We report that depletion or acute inhibition of checkpoint kinase 1 (Chk1) is sufficient to restore gamma-radiation-induced apoptosis in p53 mutant zebrafish embryos. Surprisingly, caspase-3 is not activated prior to DNA fragmentation, in contrast to classical intrinsic or extrinsic apoptosis.

Vesicular glutamate transporter 3 is required for synaptic transmission in zebrafish hair cells.

Hair cells detect sound and movement and transmit this information via specialized ribbon synapses. Here we report that asteroid, a gene identified in an ethylnitrosourea mutagenesis screen of zebrafish larvae for auditory/vestibular mutants, encodes vesicular glutamate transporter 3 (Vglut3). A splice site mutation in exon 2 of vglut3 results in a severe truncation of the predicted protein product and morpholinos directed against the vglut3 ATG start site or the affected splice junction replicate the asteroid phenotype.

Large-scale mapping of mutations affecting zebrafish development.

Background: Large-scale mutagenesis screens in the zebrafish employing the mutagen ENU have isolated several hundred mutant loci that represent putative developmental control genes. In order to realize the potential of such screens, systematic genetic mapping of the mutations is necessary. Here we report on a large-scale effort to map the mutations generated in mutagenesis screening at the Max Planck Institute for Developmental Biology by genome scanning with microsatellite markers.